// 封装购物车模块

import { defineStore } from 'pinia'
import { ref ,computed} from 'vue'
import { useUserStore } from './user'
import { insertCartAPI,findNewCartListAPI,delCartAPI } from '@/apis/cart'

export const useCartStore = defineStore('cart', () => {
  const userstore = useUserStore();
  const isLogin = computed(()=>userstore.userInfo.token)

  //更新数据
  const updateCartList = async () => {
      const res = await findNewCartListAPI()
      cartList.value = res.result
  }
  // 1. 定义state - cartList
  const cartList = ref([])
  // 2. 定义action - addCart
  const addCart = async (goods) => {
    const { skuId, count } = goods
    if(isLogin.value){
      await insertCartAPI({ skuId, count })
      updateCartList()
    }else{
      // 添加购物车操作
    // 已添加过 - count + 1
    // 没有添加过 - 直接push
    // 思路：通过匹配传递过来的商品对象中的skuId能不能在cartList中找到，找到了就是添加过
    const item = cartList.value.find((item) => goods.skuId === item.skuId)
    if (item) {
      // 找到了
      item.count+=goods.count
    } else {
      // 没找到
      cartList.value.push(goods)
    }
    }

    
  }

  // 删除购物车
  const delCart = async (skuId) => {
    if(isLogin.value){
      await delCartAPI([skuId])
      updateCartList()
    }else{
    // 思路：
    // 1. 找到要删除项的下标值 - splice
    // 2. 使用数组的过滤方法 - filter
    const idx = cartList.value.findIndex((item) => skuId === item.skuId)
    cartList.value.splice(idx, 1)
    }
}
  //清空购物车
  const clearCart = ()=>{
    cartList.value = []
  }
  // 计算属性 总的数量
  const allCount = computed(()=>cartList.value.reduce((a,c)=>a+c.count,0))
  // 计算属性 总的价格
  const sum = computed(()=>cartList.value.reduce((a,c)=>a+c.count*c.price,0))
  

  // 单选功能
  // 通过skuId找到要修改的那一项 然后把它的selected修改为传过来的selected
  const singleCheck = (skuId, selected) => {
    const item = cartList.value.find((item) => item.skuId === skuId)
    item.selected = selected
  }

  // 全选功能action
  const allCheck = (selected) => {
    // 把cartList中的每一项的selected都设置为当前的全选框状态
    cartList.value.forEach(item => item.selected = selected)
  }


  // 是否全选计算属性
  const isAll = computed(() => cartList.value.every((item) => item.selected))

  // 3. 已选择数量
  const selectedCount = computed(() => cartList.value.filter(item => item.selected).reduce((a, c) => a + c.count, 0))
  // 4. 已选择商品价钱合计
  const selectedPrice = computed(() => cartList.value.filter(item => item.selected).reduce((a, c) => a + c.count * c.price, 0))
  return {
    cartList,
    selectedCount,
    selectedPrice,
    allCheck,
    addCart,
    delCart,
    clearCart,
    allCount,
    updateCartList,
    isAll,
    sum,
    singleCheck
  }
}, {
  persist: true,
})